New method can detect contaminants in life-saving drug

Washington, Nov 18 (IANS) A simple, inexpensive method for detecting contaminants in heparin has been devised by Michigan University researchers.Heparin, a blood-thinning drug, although very effective against clots in veins, arteries and lungs, was under a cloud when contaminated samples caused serious allergic reactions resulting in many deaths.

The method relies on potentiometric polyanion sensors originally developed in Michigan University (MU) researcher Mark Meyerhoff’s lab as a tool for detecting heparin in blood.

In the latest work, Meyerhoff and coworkers show that the disposable sensors also can be used to distinguish pure heparin from heparin that is tainted with small quantities of oversulfated chondroitin sulfate (OSCS), the culprit in the recent deaths, said an MU release.

“In this technique, the magnitude of the voltage you get from the sensing membrane is dependent on polyion charge density,” Meyerhoff said, “and because the contaminant has a higher charge density than heparin, the method allows us to detect the contaminant in the presence of excess heparin.”

The new method is simpler and less expensive than analytical methods such as nuclear magnetic resonance (NMR) and capillary electrophoresis (CE), which have been suggested for detection of OSCS contaminants.

Meyerhoff, professor of chemistry, envisions the procedure being used on site in drug manufacturing plants to screen raw materials or finalised, biomedical grade heparin products for contaminants.